1. Field of the Invention
The invention relates to an optical fiber connector and adapter, and more particularly, to an optical fiber connector and adapter with keyed features.
2. Description of the Related Art
Optical fibers terminated by connectors and the adapters which are adapted to receive these connectors are an important part of virtually any fiber optical communication systems. For example, such connectors and adapters may be used to interconnect fiber segments to create longer lengths, to connector optical fiber to active or passive devices, etc. However, in some cases, for example for security reasons or in order to better manage a telecommunications network, it is desired to physically limit the insertion of a connector into a particular adapter, and as a result prevent the transmission of data via that connector and adapter.
Referring to FIG. 1, a conventional LC type optical fiber connector 100 has a generally rectangular shape with a square cross section. The connector 100 includes a rectangular housing 110 comprised of a top side-wall 111, a bottom side-wall 112, a right side-wall 113 and a left side-wall 114, wherein the bottom side-wall 112 is opposite to the top side-wall 111 and connects with the right side-wall 113 and the left side-wall 114. A latch 120 is molded into the top side-wall 111 and includes a living hinge 125 which allows the tab 126 to be moved up and down in a direction perpendicular to the central axis 150-150 of the connector 100. The latch 120 includes a pair of protrusions 121 that are positioned on opposing sides of the tab 126. In addition, a ferrule 140 protrudes from the opening 116 of housing 110. A spring (not shown in the figure) is located inside the housing 110 to allow the ferrule 140 to move back and forth through the opening 111. A pair of protrusions 160 is positioned on the right side-wall 113 and left side-wall 114, respectively.
Referring to FIG. 2, a conventional LC type optical fiber adapter 200, such as an LC duplex adapter includes a generally rectangular housing 210. The housing 210 has an axial cavity defined by a top side-wall 211, a bottom side-wall 212, a right side-wall 213 and a left side-wall 214. The axial cavity is divided into two halves by a compartment wall 215 that is parallel to the right side-wall 213 and left side-wall 214 and connects with the top side-wall 211 and bottom side-wall 212. The half of the axial cavity defined by the top side-wall 211, bottom side-wall 212, compartment wall 215 and right side-wall 213 is named as the right axial cavity and the other half of the axial cavity defined by the top side-wall 211, bottom side-wall 212, compartment wall 215 and left side-wall 214 is named as the left axial cavity. Each of the right and left axial cavities has an opening 208. A pair of indentations 220 mating with the protrusions 160 on the connector 100 is arranged in the left axial cavity on the left side-wall 214 and compartment wall 215, respectively. Similarly, the indentations 220 are also arranged in the right axial cavity on the right side-wall 213 and compartment wall 215, respectively. When the connector 100 of FIG. 1 is fully inserted into the adapter 200 through either of the openings 208, the protrusions 160 on the connector 100 will be placed in the indentations 220. Two hollow cylinders 240 are axially positioned in the right and left axial cavities respectively to receive the ferrule 140 of the connector 100. In addition, the adapter 200 further includes reciprocal locking mechanisms 230 which, referring to FIG. 1, mate with the latch 120, thereby securely interlocking the connector 100 with the adapter 200 when the connector 100 is completely inserted into the adapter 200.
In order to solve the above problem, some manufacturers change the cylinder 240 of the adapter 200 from the round cross-sectional shape to a particular shape. With such design, only a connector that the opening of the housing thereof has a shape mating with the cylinder 240, like one shown in FIG. 1, can be fully inserted into the adapter 200. The object of physically limiting the insertion of a connector into a particular adapter can therefore be achieved.
However, if one user inadvertently inserts an unmated connector into the adapter 200, the user cannot notice until a great part of the connector is inserted into the adapter 200. This will therefore increase the risk of damage to them.
Accordingly, there exists a need to provide an optical fiber connector and adapter to solve the above-mentioned problems.